The present invention relates to a container for storing and dispensing a fluid, and to a fluid level display apparatus for use with a fluid storage container. More particularly, the present invention relates to a fluid storage container including a fluid level display apparatus, and to a fluid level display apparatus including a plurality of capillary tubes.
Within the automotive field, many engine fluids are measured through the insertion of a dipstick into a fluid container or reservoir. By way of example, dipsticks are typically used for measuring power steering fluid, motor oil, and transmission fluid.
Other motor vehicle fluids may be measured by visual examination, i.e. by an individual either removing the lid of a fluid container and looking inside the container to observe the fluid level, or by the provision of a translucent or semi-translucent container body, used in combination with a colored fluid. Such a combination of a translucent container body and colored fluid allows an observer to note the fluid level by looking at the outside of the tank. Vehicular fluids measurable by this second method include windshield washer solvent, engine coolant, and brake fluid.
A modern trend in the design of motor vehicles has been toward using virtually all available space within an engine compartment, which may reduce the amount of space in which a fluid reservoir may be conveniently mounted for visual observation. Therefore, there is a tendency to place fluid reservoirs in partially hidden locations, which results in only the filler neck remaining visible. However, it remains important for a driver and/or for vehicle service personnel to monitor the vehicle fluids, in order to ensure that they are maintained at recommended levels, in order to minimize the likelihood of component failure.
In response to the ongoing need to monitor fluid levels within a container or reservoir, some level sensing devices for displaying the fluid level within a container or reservoir have been developed. Some known devices for monitoring and/or displaying a fluid level within a container or reservoir are illustrated in U.S. Pat. Nos. 3,120,125; 3,548,657; 4,213,338; 5,808,187; and 6,173,609, which are discussed further below.
Vasel, U.S. Pat. No. 3,120,125, entitled, xe2x80x9cLiquid Level Determining Device and Method,xe2x80x9d discloses a method for determining the level of a liquid in a container, using an optical transilluminating means which directs light into and through the container in an attempt to detect the level of a liquid.
Panerai et al., U.S. Pat. No. 3,548,657, entitled, xe2x80x9cDevice For An Outside Display Of The Level Of A Liquid Contained Within A Tank,xe2x80x9d discloses a container with optical light transmitting elements within a vertical wall thereof, and a light source. The device of Parnerai et al. visually displays the level of liquid in a container as a result of contact from the light source to the optical light transmitting elements.
Hardy, U.S. Pat. No. 4,213,338, entitled, xe2x80x9cLiquid Level Indicator,xe2x80x9d discloses an indicator for the amount of liquid in a dishwasher rinse aid dispenser tank. The Hardy invention incorporates a drain tube extending from the bottom of the tank, which tube is observable through a window in an interior wall of a dishwasher, to serve as a visual indicator for the level of liquid in the tank.
Gooden et al., U.S. Pat. No. 5,808,187, entitled, xe2x80x9cFluid Level Indicator,xe2x80x9d discloses a fluid reservoir including a sealed standpipe for measuring the level of fluid contained therein. The Gooden et al. invention provides a visual indication as to the level of fluid in a reservoir while filling the reservoir by selectively permitting the fluid to overflow into the center of the standpipe, thereby illustrating to a person that the reservoir is full.
Modlin et al., U.S. Pat. No. 6,173,609, entitled, xe2x80x9cOptical Level Sensor,xe2x80x9d discloses an optical sensor for visually displaying the level of fluid within a given container. The Modlin et al. invention incorporates waveguides for measuring the amount of light capable of traveling through the fluid, which correlates to the level of fluid within the container, as displayed by the optical sensor.
While each of the aforementioned inventions provides a device for measuring fluid levels within a container or reservoir, a need still exists in the art for an improved fluid storage tank apparatus, capable of passively displaying the fluid level therein. Ideally, a fluid level display apparatus would allow an observer to see an indicator of a fluid level in the container, even though the main tank body may be hidden from view.
The present invention has been developed to overcome limitations and disadvantages of the prior art, and to generally fulfill a need in the art for a simple and reliable fluid storage tank, usable in a motor vehicle, which passively displays the level of fluid therein in a way that is easily observable to a user thereof.
A fluid storage apparatus in accordance with a first embodiment of the present invention includes a main tank body including at least one side wall defining a substantially watertight chamber for storing a fluid. The tank may include multiple side walls, as desired. The tank may be molded in a cylindrical shape, or any other shape custom formed to accommodate the available space within a designated portion of a vehicle""s engine compartment. Although the storage tank hereof may remain confined to a relatively inaccessible location, which is not easily viewable, a section of the storage tank neck remains accessible from the top of the engine compartment to allow refilling.
The tank body further has a filler neck and a removable cap for containing fluid within the watertight chamber, and for providing access to allow filling of the chamber. The tank also includes a display assembly, including a plurality of capillary tubes of varying lengths. The capillary tubes extend to different fluid levels within the tank body. Preferably, the tank has an aperture formed within a wall of the chamber, to provide an outlet for dispensing the fluid.
Accordingly, it is an object of the present invention to provide a method and apparatus for passively displaying a fluid level within a hollow fluid storage tank.
It is a second object of the invention to provide a fluid storage tank having a passive fluid level display assembly, including indicia for visually showing a current fluid level therein.
It is a third object of the invention to provide a fluid level display assembly including a plurality of capillary tubes of varying lengths, which extend downwardly from an upper part of the storage tank into the chamber at respective designated levels, and in which the designated levels are different from one another.
The capillary tubes are preferred to be substantially translucent, which provides an accurate visual assessment of the fluid level within the chamber at a glance, allowing a user to quickly see whether or not a given capillary tube contains fluid.
In a first embodiment of the invention, a plurality of substantially translucent capillary tubes are independent of the side walls of the fluid storage tank, and are secured thereto. In this embodiment, the capillary tubes may reside entirely within the chamber of the fluid storage tank. Alternatively, in this embodiment, the tubes may be partially routed outside of the tank, to provide a more easily viewed visual signal. The tubes may be made clear or semi-translucent.
In a modified embodiment of the invention, multiple translucent capillary tubes of different colors are provided, and these different colors symbolize the different levels of fluid within the chamber of the fluid storage tank.
In another embodiment of the invention, multiple translucent capillary tubes are provided, with at least part of said tubes being integrally formed within a sidewall of the fluid storage tank. These capillary tubes extend from predetermined inlet locations within the chamber to a point proximate an upper portion of the fluid storage tank.
Other objects, advantages and salient features of the invention will become apparent from the following detailed description which, in conjunction with the annexed drawings, discloses the presently preferred embodiments of the invention.